| 1. |
- Cirenajwis, Helena, et al.
(författare)
-
Molecular stratification of metastatic melanoma using gene expression profiling: prediction of survival outcome and benefit from molecular targeted therapy.
- 2015
-
Ingår i: Oncotarget. - : Impact Journals, LLC. - 1949-2553. ; 6:14, s. 12297-12309
-
Tidskriftsartikel (refereegranskat)abstract
- Melanoma is currently divided on a genetic level according to mutational status. However, this classification does not optimally predict prognosis. In prior studies, we have defined gene expression phenotypes (high-immune, pigmentation, proliferative and normal-like), which are predictive of survival outcome as well as informative of biology. Herein, we employed a population-based metastatic melanoma cohort and external cohorts to determine the prognostic and predictive significance of the gene expression phenotypes. We performed expression profiling on 214 cutaneous melanoma tumors and found an increased risk of developing distant metastases in the pigmentation (HR, 1.9; 95% CI, 1.05-3.28; P=0.03) and proliferative (HR, 2.8; 95% CI, 1.43-5.57; P=0.003) groups as compared to the high-immune response group. Further genetic characterization of melanomas using targeted deep-sequencing revealed similar mutational patterns across these phenotypes. We also used publicly available expression profiling data from melanoma patients treated with targeted or vaccine therapy in order to determine if our signatures predicted therapeutic response. In patients receiving targeted therapy, melanomas resistant to targeted therapy were enriched in the MITF-low proliferative subtype as compared to pre-treatment biopsies (P=0.02). In summary, the melanoma gene expression phenotypes are highly predictive of survival outcome and can further help to discriminate patients responding to targeted therapy.
|
|
| 2. |
- Glodzik, Dominik, et al.
(författare)
-
Comprehensive molecular comparison of BRCA1 hypermethylated and BRCA1 mutated triple negative breast cancers
- 2020
-
Ingår i: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 11:1
-
Tidskriftsartikel (refereegranskat)abstract
- Homologous recombination deficiency (HRD) is a defining characteristic in BRCA-deficient breast tumors caused by genetic or epigenetic alterations in key pathway genes. We investigated the frequency of BRCA1 promoter hypermethylation in 237 triple-negative breast cancers (TNBCs) from a population-based study using reported whole genome and RNA sequencing data, complemented with analyses of genetic, epigenetic, transcriptomic and immune infiltration phenotypes. We demonstrate that BRCA1 promoter hypermethylation is twice as frequent as BRCA1 pathogenic variants in early-stage TNBC and that hypermethylated and mutated cases have similarly improved prognosis after adjuvant chemotherapy. BRCA1 hypermethylation confers an HRD, immune cell type, genome-wide DNA methylation, and transcriptional phenotype similar to TNBC tumors with BRCA1-inactivating variants, and it can be observed in matched peripheral blood of patients with tumor hypermethylation. Hypermethylation may be an early event in tumor development that progress along a common pathway with BRCA1-mutated disease, representing a promising DNA-based biomarker for early-stage TNBC.
|
|
| 3. |
- Nilsson, Martin P., et al.
(författare)
-
Germline mutations in BRCA1 and BRCA2 incidentally revealed in a biobank research study : experiences from re-contacting mutation carriers and relatives
- 2018
-
Ingår i: Journal of Community Genetics. - : Springer Science and Business Media LLC. - 1868-310X .- 1868-6001. ; 9:3, s. 201-208
-
Tidskriftsartikel (refereegranskat)abstract
- Once an incidental finding (IF) is discovered in the course of genomic research, the researchers are faced with the question of whether or not that finding should be reported back to the study participant. A large number of hypothetical studies and policy documents on this issue have been published, but there are very few empirical studies to inform the bioethics debate. Within a biobank research study of somatic mutations in breast carcinomas, ten germline BRCA1/2 mutations were incidentally detected. After thorough discussions within a group of experts, the mutation carriers (n = 7) or relatives of deceased carriers (n = 3) were re-contacted and informed about the findings. Eight out of ten accepted to receive the information and underwent confirmatory testing. One year later, semi-structured interviews were undertaken with three of the study participants. All of them felt that BRCA mutations discovered in the course of research should be reported back to the individual study participants. In this paper, we report our step-by-step experiences of the re-contacting process. We hope that our detailed reporting will be helpful for other researchers and clinicians that are faced with similar situations. The results of our study lend empirical support to opinion that IFs that meet the three baseline criteria of analytic validity, clinical significance, and actionability should be reported back to the individual study participants.
|
|
| 4. |
- Pilheden, Mattias, et al.
(författare)
-
Duplex sequencing uncovers recurrent low-frequency cancer-associated mutations in infant and childhood KMT2A-rearranged acute leukemia
- 2022
-
Ingår i: HemaSphere. - : Wolters Kluwer. - 2572-9241. ; 6:10
-
Tidskriftsartikel (refereegranskat)abstract
- Infant acute lymphoblastic leukemia (ALL) with KMT2A-gene rearrangements (KMT2A-r) have few mutations and a poor prognosis. To uncover mutations that are below the detection of standard next-generation sequencing (NGS), a combination of targeted duplex sequencing and NGS was applied on 20 infants and 7 children with KMT2A-r ALL, 5 longitudinal and 6 paired relapse samples. Of identified nonsynonymous mutations, 87 had been previously implicated in cancer and targeted genes recurrently altered in KMT2A-r leukemia and included mutations in KRAS, NRAS, FLT3, TP53, PIK3CA, PAX5, PIK3R1, and PTPN11, with infants having fewer such mutations. Of identified cancer-associated mutations, 62% were below the resolution of standard NGS. Only 33 of 87 mutations exceeded 2% of cellular prevalence and most-targeted PI3K/RAS genes (31/33) and typically KRAS/NRAS. Five patients only had low-frequency PI3K/RAS mutations without a higher-frequency signaling mutation. Further, drug-resistant clones with FLT3D835H or NRASG13D/G12S mutations that comprised only 0.06% to 0.34% of diagnostic cells, expanded at relapse. Finally, in longitudinal samples, the relapse clone persisted as a minor subclone from diagnosis and through treatment before expanding during the last month of disease. Together, we demonstrate that infant and childhood KMT2A-r ALL harbor low-frequency cancer-associated mutations, implying a vast subclonal genetic landscape.
|
|
| 5. |
- Roswall, Pernilla, et al.
(författare)
-
Microenvironmental control of breast cancer subtype elicited through paracrine platelet-derived growth factor-CC signaling
- 2018
-
Ingår i: Nature Medicine. - : Springer Science and Business Media LLC. - 1546-170X .- 1078-8956. ; 24, s. 463-473
-
Tidskriftsartikel (refereegranskat)abstract
- Breast tumors of the basal-like, hormone receptor-negative subtype remain an unmet clinical challenge, as there is high rate of recurrence and poor survival in patients following treatment. Coevolution of the malignant mammary epithelium and its underlying stroma instigates cancer-associated fibroblasts (CAFs) to support most, if not all, hallmarks of cancer progression. Here we delineate a previously unappreciated role for CAFs as determinants of the molecular subtype of breast cancer. We identified paracrine crosstalk between cancer cells expressing platelet-derived growth factor (PDGF)-CC and CAFs expressing the cognate receptors in human basal-like mammary carcinomas. Genetic or pharmacological intervention of PDGF-CC activity in mouse models of cancer resulted in conversion of basal-like breast cancers into a hormone receptor-positive state that enhanced sensitivity to endocrine therapy in previously resistant tumors. We conclude that specification of breast cancer to the basal-like subtype is under microenvironmental control and is therapeutically actionable.
|
|
